Metal cleaning compositions, baths and method



United States Patent 3,367,798 lVilETAL CLEANHNG COMPUSITIONS, BATHS ANDMETHOD Clarence Ererner, Rutherford, and Samuel S. Frey, Elizahath,N..l., assignors to ()alnite Products, Inc., New York, N.Y., acorporation of New York No Drawing. Continuation-in-part of applicationSer. No. 672,862, July 19, 1957. This application Jan. 19, 1965, Ser.No. 426,673

13 Claims. (Cl. 134-1) This is a continuation-in-part of our co-pendingapplication Ser. No. 672,862, filed July 19, 1957, now abandoned.

This invention is that of water-soluble alkaline compositions containingas their essential ingredients (i) at least one of the specific loweralkanolamines, namely, monoethanolamine, N aminoethyl monoethanolamine,and N-methyl diethanolamine; (ii) a soap made from reacting therecovered mixed fatty acids from tall oil (which acids are describedmore fully below) with at least one of these specific alkanolamines, andin such a ratio as to leave an excess of said free alkanolamine reactant(a) to serve as the aforesaid lower alkanol ingredient of the finalcomposition, and (b) to the extent of less than a mole of said freealkanolamine ingredient per mole of soap ingredient; and (iii) awater-soluble metasili cate in such amount that from about 0.7 to about1.3 ounces of it is contained per gallon of a dilute aqueous bathprepared by dissolving in water from about two to about four ounces byweight. of the overall composition (i.e. containing the freeethanolamine, the soap, and the water soluble metasilicate) per gallonof said bath solution; said free alkanolamine ingredient content alsobeing such that said aqueous bath solution prepared from the aforesaidabout two to about four ounces of this overall composition by weight pergallon of resulting dilute bath solution has a pH of from about 9 toabout 11.

Such aqueous alkaline (cleaning) bath generally can remove within a fewminutes, and often in about and even under a minute, incrustations ofbufi'ing compounds from recesses, crevices and grooves on rigidarticles, upon subjecting them immersed in said aqueous bath solution tothe influence of waves of ultrasonic frequency of from about fifteen toabout forty kilocycles per second.

The invention includes also such dilute aqueous alkaline (cleaning)baths prepared by dissolving any of these water-soluble and alkalinelower alkanolamine, metasilicate and soap containing compositions inwater in a concentration as above-noted, whereby these baths areeffective jointly with application of the ultrasonic waves foradvantageously cleaning of adherent water-insoluble dirt or soilincrustations, including those of buifing compounds, from deformationssuch as crevices, grooves and recesses on various kinds of rigidarticles or metal products.

Another part of the invention is the method of ultrasonic wave cleaningof such incrusted dirt or soil from articles or metal products bysubmerging them with such adherent dirt and incrustations in theseaqueous alkaline baths and thus subjecting such various soiled productsor articles to the influence of waves of ultrasonic frequencytransmitted within the above-indicated range through the aqueousalkaline cleaning bath.

Many metal parts or other fabricated products, as those of Zinc, copper,aluminum, brass, and antimony-lead fre quently are subjected to afinishing treatment to apply a protective or decorative coating such aslacquering 0r electroplating before they are ready for sale. Inpractically all cases for such further treatment, the article or productmust have a clean and polished surface for the lacquer coating orelectrodeposit or other coating to be reliably adherent. In preparingsuch articles or products for such coatings, it is a common practiceparticularly with electrodeposits, for example, to subject them tobuifing or polishing and with the use of the usual butting compounds.

These procedures leave these objects dirtied and soiled with toughincrustations of the bumng compound in their various surfacedeformations especially in crevices and other recessed or grooved areas.Such incrustations often are heavy and dense because of the pressuresnecessarily employed in the 'biuflirrg and polishing, and ordinarily areremoved with difiiculty and at considerable expense and disadvantage.For example, the common organic solvents usually do not remove themcompletely and otherwise take much too much time and at necessarilyincreased cost.

The same occurs with attempts in using ordinary detergents, soaps, andalkaline cleaners; and even various special formulated soap anddetergent solutions require very high temperatures often at or near thatof boiling water. These various drastic conditions frequently causecorrosion and staining of the metal objects particularly with thesensitive metals, for example, non-ferrous metals and alloys such aszinc, brass, copper, aluminum, antimony-lead, and the like. Ultrasoniccleaning also was not available or applicable because the availabletransducers could not be used at such required temperatures thatexceeded to F.

These various shortcomings and disadvantages are overcome by the methodof the invention by the use of the compositions and baths constitutingpart of the invention.

Considered broadly, the water-soluble alkaline (concentrate)compositions of the invention comprise (i) at least one of the specificlower alkanolamines selected from monoethanolamine, N-aminomethylmonoethanolamine, and Nmethyl diethanolamine; (ii) a soap of at leastone of said lower alkanolamines reacted with the recovered mixed fiattyacids of tall oil, with the latter and the alkanolaminereactant soproportioned to one another (a) to leave an excess of less than one moleof said lower alkanolamine-reactant per mole of the resulting soap, and(b) to serve as the aforesaid free alkanolamine ingredient of the finalcomposition; and (iii) a water-soluble metasilicate in such amount thatfrom about 0.7 to about 1.3 ounces of its is contained per gallon of adilute aqueous bath prepared by dissolving in water from about two toabout four ounces by weight of the overall composition (i.e. containingthe free ethanolamine, the soap, and the water-soluble metasilicate) pergallon of said bath solution; said free alkanolamine ingredient contentalso being such as to provide a pH from about nine to about eleven whenthe said overall composition of the invention is so dissolved in waterper gallon of resulting aqueous bath solution.

The ultrasonic wave cleaning baths of the invention comprise any of theforegoing water-soluble alkaline compositions of the invention dissolvedin water to a concentration of from about two to about four ounces (byweight) per gallon of aqueous alkaline bath solution.

Then the method of the invention comprises submerging soiled rigidobjects or metal articles to be cleaned in an aqueous alkaline(cleaning) bath having a pH from about 9 to about 11 by containingdissolved therein from about two to about four ounces (by weight) of a(concentrate) composition of the invention per gallon of said (cleaning)bath, and subjecting the so submerged articles to the influence of wavesof ultrasonic frequency, in the range of from about fifteen to fortykilocycles per second, transmitted to the articles through said aqueouscleaning bath, and advantageously at an elevated temperature below about160 F. and preferably under about 150 F., and for a time sutficient forthe articles to be cleaned. That generally may be within about two andone-half minutes, and so far as presently noted often about one minute.

It is highly advantageous not only as to actual operating benefits 'butalso economically to use as the soap ingredient of the water-solublealkaline (concentrate) compositions of the invention the soap preparedby reacting one or more of the aforesaid specific alkanolamines with therecovered mixed fatty acids from tall oil.

It is a significant feature of the invention that its compositions andbaths and method including the metasilicate ingredient markedly reducethe time needed to obtain complete cleaning of incrusted soil from thedeformations in the articles treated over that taken when treating thelikewise soiled same articles by the same conditions except that thecomposition and bath contain no metasilicate.

By recovered mixed fatty acids from tall oil as used herein is meantgenerically the mixed acids product obtained in the tall oil industryfrom tall oil, and therein called tall oil fatty acids. This productgenerally contains as by far its major portion, ordinarily exceedingeightyfive (85%) percent and more often being over ninety (90%) percent,the unsaturated fatty acids, namely (a) oleic acid and (b) linoleicacid, in roughly about equal parts and more often with the oleic acid inslight excess, with both of them generally amounting to betweeneightyfive (85%) and ninety-five (95%) percent of all the acids thereto,and (c) linolenic acid from none up to possibly about five percent ofthe product, together with a small amount of saturated fatty acidsusually under five (5%) percent, sometimes as little as two (2%)percent, even as low as one (1%) percent, and often between two andthree percent, and also a small percentage substantially less than tenpercent, most often not exceeding five (5%) percent, and usually four(4%) percent and even much less of rosin acids.

Typical examples of recovered mixed fatty acids from tall oil useful inpreparing the soaps for the water-soluble alkaline compositions of theinvention are, with their percentages being by weight:

' Oleic acid 47 Linoleic 40 Linolenic acid 5 Saturated fatty acids 3Rosin acids 4 Unsaponifiables 1 Oleic acid 53.7 Linoleic acid 41.3Saturated fatty acids 1 Rosin acids 5 Linoleic acid 44.16 Oleic acid48.29 Saturated fatty acids 3.55 Rosin acids 4.0

The preparation of the specific lower alkanolamine soaps of therecovered mixed fatty acids from tall oil, as included in thewater-soluble alkaline compositions, as well as of said compositions, ofthe invention is illustrated by, but not restricted to, the followingexamples using the above Example C composition of the recovered mixedfatty acids from tall oil.

Example 1.M0n0ethan0lamine soap 0 the recovered fatty acids from tall0il.One hundred and fifty milliliters of water were heated to betweenand F. in a 600 milliliter stainless steel beaker and one hundredmilliliters of technical monoethanolamine (sp. gr. 1.02) were stirred inwith a high speed mixer. While con- Zinuing the mixing, fiftymilliliters of the foregoing Example C composition of recovered mixedfatty acids from tall oil (sp. gr. 0.86) were added dropwise from a separatory funnel, at a rate such that the reaction mixture was maintainedwithin the foregoing temperature range by the heat of reaction. Afterall of this required quantity of these mixed acids were added, thestirring was continued at very high speed for several minutesthereafter. The finished product was a liquid containing themonoethanolamine soap of said recovered tall oil acids and some freeunreacted monoethanolamine dissolved in about fifty percent of water;and is a water-soluble alkaline (concentrate) composition.

Example 2.-Water soluble (concentrate) alkaline composition containing ametasilicate.To eighteen ounces by weight of the alkaline (concentrate)product of Example 1, being stirred at between 150 and 160 F. there wereadded six ounces of sodium metasilicate, and the stirring continued tillit was dissolved therein. That then provided a water-soluble(concentrate) alkaline composition of the invention.

The ultrasonic wave (dilute) aqueous alkaline cleaning baths then areprepared by dissolving in water an amount of the finished soapcomposition, for example, of the foregoing Example 2 or of anyhereinbelow described modifications of it or of any mixture of any ofthose products, sufficient to produce a pH of from about nine to abouteleven in the resulting (so diluted) aqueous alkaline cleaning bath.

Expressed otherwise, the ultrasonic wave (dilute) aqueous alkalinecleaning baths of the invention should contain by weight from about twoto about four ounces of finished alkanolamine soap, free alkanol andmetasilicate containing concentrate, that is to say, the water-solublealkaline (concentrate) composition of the various examples of suchcompositions, per gallon of (the dilute) aqueous alkaline cleaning bath.

In general, the alkalinity of such dilute cleaning bath results from itscontaining the metasilicate ingredient and on the average aconcentration of about 0.025 molal equivalent of the specificalkanolamine which was used in the preparation of the originalwater-soluble alkaline concentrated soap composition (containing theunreacted free alkanolamine). Such dilute aqueous alkaline ultrasonicwave cleaning bath is illustrated by, but not restricted to, thefollowing and other below given examples:

Example 3.Dilute aqueous alkaline bath (containing metasiIicate).-Threeounces by weight of the finished concentrate product of Example 2,containing dissolved in its water content the monoethanolamine soap ofrecovered tall oil mixed fatty acids, residual free monoethanolamine,and sodium metasilicate were dissolved in a further quantity of water tomake a gallon of dilute aqueous alkaline ultrasonic wave bath (i.e. adilute solution of the product of Example 2).

(a) For comparison, there was prepared an ultrasonic wave dilute aqueousalkaline bath from the concentrate product of Example 1, thus: Threeounces by weight of the finished concentrate liquid product of Example1, containing dissolved in its water content only its monoethanolaminesoap of the recovered tall oil mixed fatty acids and the residual freeunreacted monoethanolamine.

were dissolved in a further quantity of Water sufficient to make agallon of a dilute aqueous alkaline ultrasonic wave bath (Le. a dilutesolution of the product of EX- ample l).

The ultrasonic wave cleaning method of the invention is illustrated by,but not restricted to, the following wherein there were cleanedincrustation-soiled metal articles, specifically die castings of theZinc alloy designated as Zamak #3 alloy (containing 3.5-4.3 aluminum,0.1% copper, less than 0.1% iron, 0.030.08% magnesium, less than 0.005%of each of cadmium, lead, and sulfur, and the balance zinc to make atotal of 100%). These castings were all of the same shape, three incheslong with one side having a continuous series of V-shaped grooves eachone-sixteenth inch deep, and spaced twenty grooves to the inch oflength.

Each of the castings was buffed by means of a soft stitchless rotatingbuff until all of the grooves were packed with the tripoli buffingcomposition used (designated Formax T6, and containing between sixty andSeventy percent of abrasive essentially tripoli, from Western Missouri,and the balance a binder consisting of buffing compound waxes andgreases and stearin to the extent of twenty to fifteen percent of theentire composition of the buffing compound). The buffed castings wereset aside and left alone to age for at least five days before beingtreated by the process of this invention.

Example 4.Ultrasonic cleaning method of the inventi0n.-Five hundredmilliliters of each different dilute ultrasonic wave cleaning bath wereplaced alone in its own respective tall, liter beaker, and heated on ahot plate to 150 P. Then these beakers were put in a tank containingwater held at 150 F. by thermostatic control. Each of these beakers washeld in the tank water with its open top extending above the Water leveland with the top surface of the cleaning bath in each of them below thelevel of the Water in the tank.

The bottoms of the beakers extended to one inch above a pair of bariumtitanate transducers (sold by the Branson Ultrasonic Corporation). A 40kilocycle per second electrical current was applied to the electrodes onthe sides of the barium titanate inside of the transducers, from anelectronic oscillatory unit rated at a capacity of 125 watts.

Up to ten castings requiring thus incrusted hurling compound to becleaned from their grooves were placed in each of the beakers containingthe respective different testing solutions. The castings in each testbeaker were given a treatment by the ultrasonic waves transmitted fromthe transducers through the Water in the tank, through the glass beakerand so through the cleaning bath, at a frequency of 40 kilocycles persecond with maximum intensity until the castings were completely (i.e.100%) clean.

The minimum time for each cleaning bath to produce this extent ofcleaning was noted separately respectively for each of them, and used asan index if the cleaning efficiency of the particular cleaning bath andof the respective water-soluble alkaline (concentrate) cleaningcomposition dissolved in it. Repeat runs were conducted for each of thesolutions tested.

It was considered that any cleaning bath that required more than onehundred and fifty seconds completely to clean these castings with theirgrooves loaded with buffing compounds as above-described, generaly mightnot be particularly desirable for commercial use and operation becauseit would delay for more than two and one-half minutes transit of thearticles to be cleaned.

By this method, the ultrasonic wave dilute alkaline cleaning bath(without any metasilicate) of paragraph (a) of Example 3 required 191seconds to reach complete cleaning.

On the other hand, the corresponding ultrasonic wave dilute cleaningbath of the first paragraph of Example 3 (differing only by itscontaining sodium metasilicate) gave complete cleaning by about 100seconds. That was accomplished without any adverse effect on the buffedluster of the castings.

That is surprising not only as to the considerable saving in time soprovided, but also because of the safety to the casting surface; for itis known that sodium metasilicate often delustres the surfaces ofarticles made of the sensitive metals, which are cleaned with aqueoussolutions of it, so that its utility with them ordinarily isquestionable and undesirable.

Correspondingly similar reductions in the complete cleaning time to soconsiderably below 150 seconds result from ultrasonic wave cleaningbaths similarly prepared from water-soluble alkaline (concentrate)compositions containing similar inclusions of sodium metasilicate in therespective alkaline liquid soap (concentrate) compositions prepared by(i) using equal volumes of the monoethanolamine and the same recoveredmixed fatty acids from tall oil but otherwise prepared as in Example 2,compared with a correspondingly modified cleaning bath without anymetasilicate, which latter required 154 seconds for complete cleaning;and

(ii) Using this same concentrate as in (i) except for the volume ofmonoethanolamine being half the volume of the tall oil acids, andcompared with the corresponding cleaning bath without any metasilicate,which latter required 158 seconds to give complete cleaning.

In the various Examples 2 through 4 and others below, suitablemodifications and substitutions can be made in any of them Within thescope of the invention. For example, the specific alkanolamine can bereplaced in part or as a whole by N-aminoethyl monoethanolamine orN-methyl diethanolamine. Likewise, the sodium metasilicate can bereplaced in part or as a Whole by some other suitable water-solublemetasilicate such as another alkali metal metasilicate or ammoniummetasilicate.

In some of the examples the alkanolamine soap may be replaced, oraccompanied, in minor part by an alkali metal soap of the recoveredmixed tall oil fatty acids of the example, such as a sodium or potassiumsoap produced with them. To illustrate, the 285 grams of the mixed fattyacids from tall oil of the following Example 5 may be added as theredescribed to a solution of a single one or more or all of suitableWater-soluble alkali metal salts, for example, trisodium phosphate,sodium tetraborate-9H O (common borax), anhydrous sodium carbonate, orsodium metasilicate, dissolved in the water and their respectivequantities and also under the conditions as therein given; and thehexylene glycol then dissolved in it and followed by solution of the Naminoethyl ethanolarnine thereof in it. Alternatively, anotherembodiment of water-soluble alkaline (concentrate) composition of theinvention is illustrated by, but not restricted to, the followingexample:

Example 5.-Following the procedure used in Example 1, 395 milliliters ofwater are heated in a two liter beaker to about 150 F. and whilestirring there are added to, and dissolved in, it grams of N-aminoethylethanolarnine, and then also 27 grams of hexylene glycol. Whilecontinuing the stirring, 285 grams of the foregoing Example Ccomposition of recovered mixed fatty acids from tall oil were addeddropwise from a separatory funnel, at such a rate that the reactionmixture was held around F. by the heat of reaction.

Thereafter there was homogeneously dissolved in the resultingN-aminoethyl ethanolamine soap (concentrate) composition (containingexcess unreacted alkanolamine), 124 grams of trisodium phosphate-12H O,80 grams of common borax, 80 grams of anhydrous sodium carbonate, and 9grams of sodium metasilicate, and the stirring was continued at highspeed for several minutes. The finished product, after discontinuing thestirring, was a watersolu=ble alkaline liquid soap (concentrate)composition containing free unreacted N-aminomethyl ethanolarnine.

An ultrasonic wave (dilute) alkaline cleaning bath containing threeounces per gallon of that final product of Example produced completecleaning of castings such as described in Example 4, by the method ofthat example, by about 80 seconds.

Where desirable, suitable surface active agents and/ or dispersingagents, that are compatible with the other ingredients of any of thecompositions covered by the invention can be included. The significantfeature of the invention is the presence in the water-soluble alkalinesoap (concentrate) compositions, of a significant quantity of thespecific free unreacted lower alkanolamine, and also the significantcontent of the metasilicate ingredient which contributes reduction incleaning time.

While the invention has been explained in detail by tile scribingcertain specific embodiments of it, it is understood that variousmodifications and substitutions may be made in any of the specificembodiments within the scope of the appended claims which are intendedalso to cover equivalents of the specific embodiments.

What is claimed is:

1. A composition useful in cleaning of soil from deformations in rigidarticles, which composition is (A) water-soluble, (B) alkaline, and (C)comprises as its essential ingredients for said cleaning utility:

(i) at least one lower alkanolamine member of the class consisting ofmonoethanolamine, N-aminoethyl monoethanolamine, and N-methyldiethanolamine;

(ii) a soap made from reacting the recovered mixed fatty acids from talloil and at least one of said alkanolamines, with said mixed acids usedin such ratio to the alkanolamine-reactant to leave an excess of thelatter to be the said specific alkanolamine ingredient (i) and to theextent of less than a mole thereof per mole of said soap ingredient and(ii) such that an aqueous solution having a pH from about 9 to about 11results when said alkanolamineand soapcontaining composition isdissolved in water in an amount from about 2 to about 4 ounces by weightper gallon of said aqueous solution; and

(iii) a water-soluble metasilicate in such concentration that from about0.7 to about 1.3 ounces of it is contained per gallon of a diluteaqueous bath prepared by dissolving in water from about 2 to about 4ounces by weight of the overall composition per gallon of said bathsolution; and said resulting dilute aqueous bath enabling completelyremoving generally within a few minutes incrustations of buffingcompounds from recesses as well as grooves on rigid articles, uponsubjecting them immersed in said dilute aqueous bath to the influence ofwaves of ultrasonic frequency of from about fifteen to about fortykilocycles per second.

2. An aqueous cleaning bath solution which is alkaline and comprises, asits essential ingredients for its below mentioned incrustation removalproperty, from about two to about four ounces by weight of an alkalinecomposition as claimed in claim 1 dissolved therein per gallon of saidaqueous bath solution; said cleaning bath having a pH of from about 9 toabout 11 and being effective at a temperature from about ambienttemperature to about 160 F. to enable complete removal of buffingcompound incrustations from recesses as well as grooves on rigidarticles immersed in said bath to occur within an interval of two andone-half minutes while subjecting them therein to the influence ofultrasonic waves of from about fifteen to about forty kilocycles persecond.

3. An aqueous cleaning bath as claimed in claim 2, wherein thealkanolamine is monoethanolamine.

'4. An aqueous cleaning bath as claimed in claim 2, wherein thealkanolamine is N-aminomethyl monoethanolamine.

5. An aqueous cleaning bath as claimed in claim 2, wherein thealkanolamine is N-methyl diethanolamine.

6. The method of removing dirt and soil incrustations, including eventhose of buffing compounds, from recesses as well as grooves on rigidarticles, which method comprises submerging such articles in an aqueousalkaline cleaning bath solution containing dissolved therein, as itsessential agents for the aforesaid incrustation removal activity, pergallon of its water from about two to about four ounces by weight of analkaline water-soluble composition as claimed in claim 1; and subjectingsuch so submerged articles to the influence of waves of ultrasonicfrequency, of the order from about fifteen to about forty kilocycles persecond, transmitted to the articles through said aqueous alkalinecleaning bath, and for a time sufficient completely to clean theincrustations from said articles and less than that required with acorresponding cleaning bath without the metasilicate and operated underotherwise like conditions.

'7. The method as claimed in claim 6, wherein the alkanolamine ismonoethanolamine.

8. The method as claimed in claim 6, wherein the alkanolamine isN-aminomethyl monoethanolamine.

9. The method as claimed in claim 6, wherein the alkanolamine isN-methyl diethanolamine.

10. A liquid, aqueous alkaline soap-containing composition comprising,as its essential ingredients for its be low mentioned incrustationremoval property, (i) the soap formed by reacting in sufficient waterabout one hundred parts of monoethanolamine and about 285 parts of therecovered mixed fatty acids of tall oil, and homogeneously dissolvedtherewith in water about 124 parts of trisodium phosphate- 121-1 0,about parts of ordinary borax, about 80 parts of anhydrous sodiumcarbonate, and about 9 parts of sodium metasilicate; the dilute aqueousalkaline bath solution resulting when said soap composition is dissolvedin water to a concentration of from about two to about four ouncesthereof by weight per gallon of resulting dilute aqueous solution, beingefiective at a temperature from about ambient temperature to about F. toenable complete removal of buffing compound incrustations from recessesand grooves on rigid articles while subjecting said articles submergedin said bath solution to the influence of ultrasonic waves of from aboutfifteen to about forty kilocycles, to occur in less time than suchcomplete removal can occur when sodium metasilicate isomitted.

11. A liquid aqueous alkaline soap-containing composition as claimed inclaim 10, wherein about 27 parts of hexyleneglycol also are dissolved insaid water.

12. An aqueous cleaning bath comprising in aqueous solution, as itsessential agents for its below mentioned incrustation removal activity,per gallon of bath solution the alkaline soap composition of claim 10 tothe extent of about two to about four ounces by weight of the contentthereof exclusive of the water used as reaction medium; said cleaningbath having a pH of from about 9 to about 11 and being effective at atemperature from about ambient temperature to about 160 F. to enablecomplete removal of bufiing compound incrustations from recesses as wellas grooves on rigid articles under the in fiuence of ultrasonic waves offrom about fifteen to about forty kilocycles per second, to occur inless time than such complete removal can occur when the sodiummetasilicate is omitted.

13. The method of removing dirt and soil incrustations, including eventhose of bur'fing compounds, from recesses as well as grooves on rigidarticles, which comprises submerging such articles in an aqueousalkaline bath as claimed in claim 10, and subjecting the articles sosubmerged to the influence of waves of ultrasonic frequency, of theorder from about fifteen to about forty kilocycles per second,transmitted to the articles through the aqueous alkaline cleaning bath,and for a time sutficient completely 0 clean the incrustations from saidarticles and less than 10 the time required therefor when sodiummetasilicate is OTHER REFERENCES omltted from Sald bath Tall oil,Pollak, Soap and Sanitary Chemicals, May

References Cited 1953, pp. 43-45, 81. UNITED STATES PATENTS 5 HexyleneGlycol, Shell Chemical Corporation, Techni- 2 374 113 4 45 Lowe 52 1 CalBooklet SC PP- 2,616,820 11/1952 Bourgeaux 134 1 X The CondensedChemical Dictionary, 5th Ed., Rose, 2,700,654 1/1955 Holman 252118 9 PP-2,888,939 6/1959 Nitsche 134-1 X 2,978,415 4/1961 Chamberlain 252--118l0 LEON D. ROSDOL, Primary Examiner.

FOREIGN PATENTS S. E. SCHNEIDER, Assistant Examiner.

548,960 10/1942 Great Britain.

1. A COMPOSITION USEFUL IN CLEANING OF SOIL FROM DEFORMATIONS IN RIGIDARTICLES, WHICH COMPOSITION IS (A) WATER-SOLUBLE, (B) ALKALINE, AND (C)COMPRISES AS ITS ESSENTIAL INGREDIENTS FOR SAID CLEANING UTILITY: (I) ATLEAST ONE LOWER ALKANOLAMINE MEMBER OF THE CLASS CONSISTING OFMONOETHANOLAMINE, N-AMINOETHYL MONOETHANOLAMINE, AND N-METHYLDIETHANOLAMINE; (II) A SOAP MADE FROM REACTING THE RECOVERED MIXED FATTYACIDS FROM TALL OIL AND AT LEAST ONE OF SAID ALKANOLAMINES, WITH SAIDMIXED ACIDS USED IN SUCH RATIO TO THE ALKANOLAMINE-REACTANT TO LEAVE ANEXCESS OF THE LATTER TO BE THE SAID SPECIFIC ALKANOLAMINE INGREDIENT (I)AND TO THE EXTENT OF LESS THAN A MOLE THEREOF PER MOLE OF SAID SOAPINGREDIENT AND (II) SUCH THAT AN AQUEOUS SOLUTION HAVING A PH FROM ABOUT9 TO ABOUT 11 RESULTS WHEN SAID ALKANOLAMINE- AND SOAPCONTAININGCOMPOSITION IS DISSOLVED IN WATER IN AN AMOUNT FROM ABOUT 2 TO ABOUT 4OUNCES BY WEIGHT PER GALLON OF SAID AQUEOUS SOLUTION; AND (III) AWATER-SOLUBLE METASILICATE IN SUCH CONCENTRATION THAT FROM ABOUT 0.7 TOABOUT 1.3 OUNCES OF IT IS CONTAINED PER GALLON OF A DILUTE AQUEOUS BATHPREPARED BY DISSOLVING IN WATER FROM ABOUT 2 TO ABOUT 4 OUNCES BY WEIGHTOF THE OVERALL COMPOSITION PER GALLON OF SAID BATH SOLUTION; AND SAIDRESULTING DILUTE AQUEOUS BATH ENABLING COMPLETELY REMOVING GENERALLYWITHIN A FEW MINUTES INCRUSTATIONS OF BUFFING COMPOUNDS FROM RECESSES ASWELL AS GROOVES ON RIGID ARTICLES, UPON SUBJECTING THEM IMMERSED IN SAIDDILUTE AQUEOUS BATH TO THE INFLUENCE OF WAVES OF ULTRASONIC FREQUENCY OFFROM ABOUT FIFTEEN TO ABOUT FORTY KILOCYCLES PER SECOND.
 6. THE METHODOF REMOVING DIRT AND SOIL INCURSTATIONS, INCLUDING EVEN THOSE OF BUFFINGCOMPOUNDS, FROM RECESSES AS WELL AS GROOVES ON RIGID ARTICLES, WHICHMETHOD COMPRISES SUBMERGING SUCH ARTICLES IN AN AQUEOUS ALKALINECLEANING BATH SOLUTION CONTAINING DISSOLVED THEREIN, AS ITS ESSENTIALAGENTS FOR THE AFORESAID INCRUSTATION REMOVAL ACTIVITY, PER GALLON OFITS WATER FROM ABOUT TWO TO ABOUT FOUR OUNCES BY WEIGHT OF AN ALKALINEWATER-SOLUBLE COMPOSITION AS CLAIMED IN CLAIM 1; AND SUBJECTING SUCH SOSUBMERGED ARTICLES TO THE INFLUENCE OF WAVES OF ULTRASONIC FREQUENCY, OFTHE ORDER FROM ABOUT FIFTEEN TO ABOUT FORTY KILOCYCLES PER SECOND,TRANSMITTED TO THE ARTICLES THROUGH SAID AQUEOUS ALKALINE CLEANING BATH,AND FOR A TIME SUFFICIENT COMPLETELY TO CLEAN THE INCRUSTATIONS FROMSAID ARTICLES AND LESS THAN THAT REQUIRED WITH A CORRESPONDING CLEANINGBATH WITHOUT THE METASILICATE AND OPERATED UNDER OTHERWISE LIKECONDITIONS.